中国现行的蛋鸡舍内CO2浓度控制的农业行业标准为1500 mg/m3，主要适用于传统的刮板式清粪鸡舍。目前新建、改建鸡舍都采用传送带清粪方式，鸡舍内的相对湿度和氨气等有害气体浓度均明显减少，其冬季最小通风量和舍内CO2浓度参数标准均有待重新研究。该文通过总结分析国内外相关学者对不同清粪方式蛋鸡舍内 NH3、CO2浓度的测试数据，提出传送带清粪蛋鸡舍内CO2浓度取值建议，并根据CO2浓度平衡原理，提出该类蛋鸡舍冬季最小通风量的取值建议。结果表明：传送带清粪蛋鸡舍内CO2浓度参数控制标准建议可取5000 mg/m3；蛋鸡舍冬季连续通风最小通风量为0.40～0.50 m3/（h·kg）。该研究为中国新建、改建传送带清粪模式蛋鸡舍CO2浓度参数标准的取值以及调控蛋鸡舍冬季通风与保温矛盾等问题提供了参考依据。%The CO2 concentration is required to be below 1500 mg/m3(Environmental Quality Standards for the Livestock and Poultry Farm of China, published in 1999) in layer hen houses where the manure is disposed by powered scraper, the litters generally need to remind and the drinking device has water leak. Consequently, moisture and NH3 levels in such barns are much high. Also, air temperature is much lower in winter, because the minimum ventilation rate is large in winter. However, the manure is cleaned daily in new poultry house with manure convey belt. Meanwhile, the aerial pollutants (CO2 and NH3) are reduced and the relative humidity is decreased. Indoor air quality in this kind of poultry house is dramatically improved. A new standard of CO2 concentration and the minimum ventilation rate of layer house with manure convey belt should be reconsidered. Determining the CO2 concentration standards for the manure convey belt in layer hen houses is needed. The objectives of this work were to draw a conclusion about the CO2concentration levels and use it as a reference to calculate the minimum ventilation rate in winter. This review summarized the recent measurements of the emission rates of aerial NH3 and the CO2 concentrations in poultry houses in which the laying hens were kept in cages. The relationship between CO2 and NH3 was also described based on the data got in the poultry houses with different manure removing way from the domestic and foreign study. In addition, the minimum ventilation rate is important for ensuring the ideal air quality in poultry house in winter. The optimum ventilation is one of the factors affecting poultry production and energy consumption. Considering the mass conservation under steady-state conditions in the layer hen building, there are 2 main sources of CO2 in poultry house, and most of the CO2 is produced by respiration processes of layer hens, if neglecting the amount of CO2 emitted from manure. The minimum temperature value for layer houses was 13℃ in this study. The following conclusions were drawn in this study: 1) There was a positive and significant correlation between CO2 and NH3 concentration in layer houses based on analyzing the data of previous researches. The standards of CO2 concentration and NH3 concentration were suggested to be 5000 mg/m3 and less than 15 mg/m3 respectively in the layer hen houses with manure convey belt. This condition would not reduce the hen’s performance and defenses. Primary CO2concentration standards persisted when the feces were scraped by powered scraper to a cross conveyor at the end of the barn; 2) Average NH3 concentrations in the layer house with manure convey belt was largely less than the traditional house with the scraper. Therefore, rebuilding new layer hen’s building equipped with the manure convey belt is crucial not only for indoor environment, but also for ventilation system; 3) Ventilation rate was calculated using the rate of laying hen in winter based on CO2 mass balances from the literature. The constantly minimum ventilation rates were 0.40-0.50 m3/(h·kg) for the layer houses with manure convey belt. The new standards of CO2 concentration and ventilation rate were beneficial for improving indoor environment control and ventilation energy efficiency, and saving constructional costs. Furthermore, the results of this paper provide the reference for solving the contradiction between ventilation and insulation system in layer house. Also, it can improve the versatility of poultry environment and provide the support for emission studies using the new standard of the CO2 to evaluate the poultry building environment.
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